Body image and health is of interest for many humans. For some, there is a need to have shapely arms, legs, pectoral and gluteal muscles and the like, often together with improved strength and overall fitness. Given the more hectic lifestyles of people in last few years, there has been an increased interest in finding simple, non-invasive and safe methods for improving the appearance and strength of a person's arms, legs, pectoral, gluteal and other muscles, without having to expend too much time and effort.
Hyaluronic acid (HA), also known as hyaluronan or hyaluronate, is a well-known, naturally occurring polysaccharide that is secreted by fibroblasts and found in all mammals. It is a long unbranched, high molecular weight polysaccharide composed of repeating dimeric units of D-glucuronic acid and N-acetylglucosamine, and is found in all tissues in the body, with higher amounts in the skin, the vitreous humor of the eye and connective tissues. When not bound to other molecules, HA binds to water and forms a highly viscous solution, giving it a jelly-like substance.
HA currently has a variety of uses, including cosmetic and therapeutic uses. With respect to therapeutic uses, HA has been used as a replacement for the liquid vitreous of the human eye to aid in ophthalmic surgery; to treat osteoarthritis, by intra-articular injection directly into the synovial fluid in the knee (for example, George (1998) Ann. Rheum. Dis. 57: 637-40; Weiss et al. (1981) Arthritis Rheum. 11 (suppl 1): 143-4); to manage and treat chronic tennis elbow or lateral epicondylosis (for example, Petrella et al. (2010) Sports Medicine, Arthroscopy, Rehabilitation, Therapy & Technology 2:4; Orchard and Kountouris (2011) BMJ (2011) 342: d2687); and to treat vocal fold paralysis by injection into the thyroarytenoid (TA) muscle of the larynx (for example, Wang et al. (2011) Journal of Voice 26(4): 506-514; Lee et al. (2010) Thyroid 20(5): 513-517). Cosmetically, HA has been used to provide facial enhancements and improve the skin's contour and reduce depressions in the skin due to acne, scars, injury or lines by subcutaneous injection, directly under a person's skin (for example, Duranti et al. (1998) Dermatol. Surg. 24: 1317-25; Jordan (2003) Can. J. Ophthalmol. 38: 285-8; Cheng et al. (2002) Otolaryngol. Clin. North Am. 35:73-85). In addition to being used as the primary agent, HA has been used as a secondary agent, such as a viscosity-inducing component (for example, Aydin et al. (2007) Auris Nasus Larynx 34(3): 333-8; US 2008/0044476), or as a biocompatible polymer (for example, KR 2008/0100126).
Recently, Macrolane™ (Q-med AB), a gel derived from HA, has been used for body contouring and breast augmentation in Europe. It has been used for reshaping and boosting volume in specific areas of the body, such as the buttocks, calves, chest muscles and arms, and filling concavities and scars on the body (see URL: stureplanskliniken.com/macrolane.asp; and familyhealthguide.co.uk/cosmetic-surgery/macrolane.html). Macrolane™ is intended solely for injection into the subcutaneous skin layer above the muscle, but not for intramuscular or intravascular injection (Q-Med AB Macrolane Clinical Guide; or see URL: myfacemybody.com/procedures/non-surgical/injectable-body-contouring-macrolane/).